Association between Visceral Adipose Tissue Metabolism and Alzheimer's Disease Pathology

Abstract

The visceral adipose tissue (VAT) has been recognized as an endocrine organ, and VAT dysfunction could be a risk factor for Alzheimer's disease (AD). We aimed to evaluate the association of VAT metabolism with AD pathology. This cross-sectional study included 54 older subjects with cognitive impairment who underwent 2-deoxy-2-[fluorine-18]-fluoro-D-glucose (¹⁸F-FDG) torso positron emission tomography (PET) and ¹⁸F-florbetaben brain PET. ¹⁸F-FDG uptake in VAT on ¹⁸F-FDG PET images was used as a marker of VAT metabolism, and subjects were classified into high and low VAT metabolism groups. A voxel-based analysis revealed that the high VAT metabolism group exhibited a significantly higher cerebral amyloid-β (Aβ) burden than the low VAT metabolism group. In the volume-of-interest analysis, multiple linear regression analyses with adjustment for age, sex, and white matter hyperintensity volume revealed that ¹⁸F-FDG uptake in VAT was significantly associated with the cerebral Aβ burden (β = 0.359, p = 0.007). In conclusion, VAT metabolism was associated with AD pathology in older subjects. Our findings suggest that VAT dysfunction could contribute to AD development.

Keywords: Alzheimer’s disease; adipose tissue; amyloid-β; glucose metabolism.

Figure 1

Flow diagram of the study population.

Figure 2

Voxel-based comparison of cerebral Aβ burden between the high and low visceral adipose tissue (VAT) metabolism groups. The statistical parameter mapping t-maps were superimposed on the volume-rendered magnetic resonance imaging (MRI) (A) and T1-weighted template in the axial plane (B) for the high VAT metabolism group > low VAT metabolism group (p < 0.005, uncorrected at voxel-level, cluster size > 100 voxels).

Figure 3

Association of visceral adipose tissue (VAT) metabolism with cerebral amyloid burden. Pearson’s correlation analysis revealed that VAT maximum standardized uptake volume (SUV_max) correlated positively with composite regional standardized ¹⁸F-FBB uptake value ratios (SUVR_FBB) (A), and all regional SUVR_FBB values in the bilateral lateral frontal (B,C), lateral temporal (D,E), and lateral parietal (F,G) cortices, as well as the bilateral cingulate cortices (H,I).